Wont send my pm's

ive been trying to send my p.m's and insted of going into my sent box it just goes into my out box. Does any one know whats up? Ive checked and there is space in my inbox, sentbox.
Thanks billy
Specialized Tarmac - Team bike
Kinesis Grand Fondo Ti - Year round training bike
Kinesis Pro 6 - CX bike
Orbea Alma 29er - MTB

Trek madone 5.2- Sold
Ragley Marley Mtb- Sold